My present mattress weighs a ton and I gave up turning it over some years ago because of this and also lack of space. I am considering a king sized version of the Origin Pocket 1500. I mentioned the possibility of a zip and link to my partner as they would each weigh half as much, but she was horrified, so I guess that option is out!! Can you tell me how much it weighs please? Are your foam mattresses any lighter? Also I don't understand how it is nominally 9" deep, but 13" if the padding is taken into account. If I took a ruler to it what depth would it actually measure?